Last week I climbed into my Tesla Model S charged with 100% solar power the day before. I know this because I now have a very sophisticated app which came with the home battery system and 5.3 kilowatt peak solar photovoltaic array I’ve just had installed.

The 13.3 kilowatt hour Tesla Powerwall was at 10% when I woke that morning, (it had drained itself into the Nissan Leaf overnight) and was refilled by midday so I used the excess solar output in the afternoon to charge the Tesla.